Study On The Device Structure Of SiCOI

In order to combine the benefits of SiC material with the advantages of SOI technology reasonably. a new 4H-SiC SiCOI(Silicon Carbide On Insulator) device structure is presented in this artcle. By making use of the 2D device simulator ISE-TCAD to analysed the kinds of electrical characteristics of SiCOI MESFET's.Firstly, according to the characteristics of SiC material,the physical models used in the simulation are presented in detail, and the parameter sets for both of the materials are set up, which provide a design platform for 4H-SiC technology and device.Secondly, on the basis of Establishing in the front SiCOI MESFET device structure and the physical model base, simulations were made on transfer characteristics of SiCOI MESFET's By employing 2D device simulator ISE-TCAD. Results showed that structure parameters have a great effect on the transfer characteristics of SiCOI MESFET's. such as: When the thickness of active layer arised from 0.13μm to 0.3μm, the threshold voltage becomed from -1V to -4.4V ;the gate length arised from 1μm to 3μm, the threshold voltage becomed from -5.5V to -4.9V ; the doping concentration arised from 8×10¹⁶/cm³ to 1.2×10¹⁷/cm³ ,and the threshold voltage becomed from -3.1V to -6.2V .This shows that the structure of the device have a significantly effect on the device's capability.Thirdly, result from the simulations were made on the output characteristics and the breakdown characteristics of SiCOI MESFET's get charateristics curves in different condition.And the result also find that reduce the gate length, heavily doping concentration and thick active layer, the output characteristics of the device were significantly improved.At last, SiCOI MESFET's temperature characteristic is simulated for a range of temperatures. Results showed that the rising device temperature have an apparent degradation of a variety of electrical characteristics.In a word, this article provides the theoretical base for further works to study the 4H-SiC SiCOI MESFET characteristics with numerical simulation.